1. Field of the Invention
This invention relates to improvements in water flow system and, more particularly, to irrigation watering sprinkler systems. The flow control device automatically shuts off the flow of water through the device when the flow exceeds a predetermined rate i.e. 120% or more of rated flow.
2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 1.98
The automatic sprinkler system is most common and widely accepted to irrigate agriculture and landscape of Local Parks, golf courses and residential households. The various types and sizes of sprinklers use billions of gallons of water every day. In the past years many people have invented excess water shutoff valve in order to prevent wasting water that is caused by a broken pipe or broken sprinkler system and head. There are numerous U.S. Patents granted for valve that limit excess flow or shutoff undesired flow. Exemplary examples of patents covering these products are disclosed herein.
U.S. Pat. No. 4,825,897 issued May 2, 1989 to Stephen A. Shade and U.S. Pat. No. 5,280,806 issued Jan. 25, 1994 to Richard J. Glazebrook discloses a Flow Control Device that uses a weighted spherical ball that is positioned in the housing which seats during subnormal fluid flow. When excessive flow occurs the ball is pushed up into pipe orifice that shuts off the flow to the irrigation head. While this patent discloses a flow control device the flow control device does not utilize a malleable elastomeric flow restricting device that collapses upon excessive flow.
U.S. Pat. No. 4,842,198 issued Jun. 27, 1989 and U.S. Pat. No. 4,867,603 issued Sep. 19, 1989 both issued to Shih-Chih Chang and U.S. Pat. No. 6,644,345 issued Nov. 11, 2003 to Robert Dullin describes a Device for Damage Protection against Local Flooding Caused by Sprinkler Failure. These devices uses a spring loaded valve which interrupts sprinkler flow when abnormal flow overpowers the spring and pushes the valve closed. While this device prevents excess flow the construction of the device does not use a malleable elastomeric collapsing structure when there is excessive flow.
U.S. Pat. No. 5,613,518 issued Mar. 25, 1997 to Kenneth E. Rakieski and U.S. Pat. No. 7,111,638 issued Sep. 26, 2006 to Dwight N. Johnson discloses an Excessive Flow Shutoff Devices that use a spring loaded plunger to shutoff excessive flow. This pending application eliminates the need for a spring by using a malleable elastomeric device that collapses when excessive flow pulls the sides of the shutoff device in to stop flow.
U.S. Pat. No. 6,363,963 issued Apr. 2, 2002 to William C. White discloses an Excess Flow Shutoff Valve. This patent discloses a flow sensitive piston that is pushed up and closes when there is excess flow through the conduit. This patent also does not disclose a malleable elastomeric collapsing device and requires a fairly complicated set of high precision components to shutoff excessive flow.
U.S. Pat. No. 6,962,165 issued Nov. 8, 2005 to Cyrille Delprat et al., discloses an Automatically-Actuated Safety Device with a Double-Seated Valve to Regulate the Flow Rate of a fluid. The flow device disclosed in this patent regulates the flow by partially deforming a plunger type device that spreads under high flow to reduce the amount of flow through the valve. This device does not stop excessive flow.
U.S. Published Application No. US 2007/0034712 published on Feb. 15, 2007 to Carl L. C. Kah Jr., discloses a Broken Sprinkler Flow Restriction or Flow Shutoff Suppressor for Sprinkler. The flow shutoff device is mounted directly under a sprinkler valve to stop flow using a spring loaded when a sprinkler is broken. This device does not collapse the flow line but uses a poppet valve to stop the flow.
What is needed is a device that is simple in construction and has a highly functionally reliable with desirable operating characteristics. The Overflow Shutoff Valve is designed to withstand surge flow of the system and this feature is not found in the cited reference patents.